Questions asked by Ciela

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• How many electrons does it take to fill all molecular orbitals formed from the 1s orbitals of 2 atoms?
  
• Find the exact value of cos​(alpha minus beta​) if sin alpha equals 0.1102 and cos beta equals 0.4111​, and both alpha and beta are​ first-quadrant angles?
  
• Sam is framing a closet under a stairway. The stairway is 18 ft 5 in.​ long, and its angle of elevation is 38 degrees. Find the depth of the closet to the nearest inch?
  
• From a hot air balloon 2 km​ high, a person looks east and sees one town with angle of depression of 16 degrees. He then looks west to see another town with angle of depression of 84 degrees. What is the distance between the two towns?
  
• Find the exact value of cos​(alpha minus beta​) if sin alpha equals 0.5276 and cos beta equals 0.3488​, and both alpha and beta are​ first-quadrant angles?
  
• Sqrt(sin^8x*cos^5x)*sqrt(cosx) What is the answer?
  
• A sample of dolomite, a carbonate mineral, contains 0.5422 mol Ca, 0.5422 mol Mg, 1.085 mol C, and 3.254 mol O. What is the empirical formula of this sample of dolomite?
  
• Structures containing the mineral magnetite are found in birds' beaks and may help them navigate. Magnetite is an oxide of iron and in a 100 g sample there are 72.36 g of iron (Fe). What is the empirical formula of this sample of magnetite?
  
• A window washer on a ladder looks at a nearby building 126 ft​ away, noting that the angle of elevation to the top of the building is 18.4 degrees and the angle of depression to the bottom of the building is 8.4 degrees . How tall is the nearby​ building?
  
• From a hot air balloon 2 km​ high, a person looks east and sees one town with angle of depression of 16 degrees. He then looks west to see another town with angle of depression of 84 degrees. What is the distance between the two towns ?
  
• A pole leans away from the sun at an angle of 5 degrees to the vertical. When the elevation of the sun is 56 degrees​, the pole casts a shadow 43 ft long on level ground. How long is the​ pole?
  
• A ranger in tower A spots a fire at a direction of 312 degrees. A ranger in tower​ B, located 40 mi at a direction of 54 degrees from tower​ A, spots the fire at a direction of 272 degrees. How far from tower A is the​ fire? How far from tower​ B?
  
• Find the exact value of cos​(alpha minus beta​) if sin alpha equals 0.5276 and cos beta equals 0.3488​, and both alpha and beta are​ first-quadrant angles?
  
• What is ln(cos x )= 0 in ​[0,2​pi)?
  
• What is the oxidizing agent in the following net ionic equation of a reaction? 4H+ (aq) + SO4^2-(aq) + 2NaI (s) --> 2 Na+ (aq) + I2 (s) + SO2 (g) + 2 H2O (l)
  
• What is the oxidation number of nitrogen (N) in HNO2?
  
• The floor of a pool in the shape of a parallelogram has sides that measure 42 ft and 59 ft. To meet the minimum required length for the shortest​ diagonal, the angles must be 61 degrees and 119 degrees. What is the lengths of the diagonals?
  
• How do you rationalize? sqrt(1+cosy)/(1-cosy)
  
• What are the solution in the interval [0, 2pie]? sec^2x-tan^2x=0
  
• (2-2i)^5 What is this in standard notation?
  
• What is the fourth root of 1296?
  
• (-1+i)/(1+i) What is this in standard notation?
  
• The pitch of the roof on a building needs to be 3/14. If the building is 38 ft​ wide, how long must the rafters​ be?
  
• On the​ earth, 49 degrees of latitude is how many​ kilometers? how many​ miles? (Assume that the radius of the earth is 6400​ km, or 4000​ mi, approximately.)
  
• What is the center, the​ vertices, and the foci of the ellipse? 9x^2+25y^2-18x+200y+ 184=0
  
• What is the center, the​ vertices, and the foci of the ellipse? 16x^2+25y^2-160x+200y+ 400=0
  
• A luggage wagon is being pulled with vector force V​, which has a magnitude of 750 pounds at an angle of elevation of 63 degrees. What is vector V in components?
  
• A block weighing 80 lb rests on a 30 degrees incline. What is the magnitude of the components of the​ block's weight perpendicular and parallel to the incline?
  
• What are the solutions of 6 tanx sinx-6 tanx=0 in the interval ​[0,2pi]?
  
• What is the equation of a parabola satisfying the given information? Focus​ (8​, 4​), directrix x= -9
  
• What is the equation of a parabola satisfying the given information? Focus​ (8​, 2) directrix x= -9
  
• There is an escalator that is 1086.8 feet long and drops a vertical distance of 195.4 feet. What is its angle of​ depression?