Help me:( identify what property of light is used in the listed optical instruments. (refraction, reflection)

1. reflector telescope
2. eyes
3. binoculars
4. magnifying glass
5. refractor telescope
6. light microscope
7. camera

Which terms describe the purpose of antennas on devices that use radio waves? transmit and receivemodify and amplifyamplify and receivemodify and transmit

Most of the volume of an atom is occupied by the

The base of a 50-meter tower is at the origin; the base of a 50-meter tree is at (0, 50, 0). the ground is flat and the z-axis points upward. the following parametric equations describe the motion of six projectiles each launched at time t = 0 in seconds. (i) r (t) = (50 + t2)k (ii) r (t) = 2t2 j + 2t2k (iii) r (t) = 50 i + 50 j + (50 − t2)k (iv) r (t) = 2t j + (50 − t2)k (v) r (t) = (50 − 2t) i + 2t j + (50 − t)k (vi) r (t) = t i + t j + tk (a) which projectile is launched from the top of the tower and goes downward? at time t = , the projectile hits the ground at point (x, y, z) = . (b) which projectile hits the top of the tree?