Agolfer on a level fairway hits a ball at an angle of 21° to the horizontal that travels 99 yd before striking the ground. he then hits another ball from the same spot with the same speed, but at a different angle. this ball also travels 99 yd. at what angle was the second ball hit? (neglect air resistance.)

69°

Explanation:

Projectiles that land at the same elevation they're launched from will have the same range if the launch angles are complementary (add up to 90°).

The complement of 21° is 69°.

  the grams     of oxygen gas   that can be produced     is 20.6   grams of o₂

calculation

2liclo₃ →   2 licl + 3 o₂

step 1:   find the moles of liclo₃

moles = mass÷ molar mass

from periodic table the molar mass of liclo₃ =6.9 +35.5   +(16 x3) =90.4 g/mol

moles=38.7 g÷90.4 g/mol=0.4281   moles

step 2:   use the   mole ratio   to calculate the moles of o2

from equation above, liclo₃: o₂   is 2: 3  

therefore the moles of   o₂=0.4281 moles x3/2 =0.6422   moles

step 3: find mass   of o₂

mass= moles x molar mass

from periodic table the   molar mass of   o₂ = 16 x2= 32 g/mol

mass=0.6422   moles   x   32 g/mol = 20.6 grams of o₂

uranium fissions/breaks up giving out energy and neutrons