<em>The convex lens is a lens that converges rays of light that convey parallel to its principal axis (i.e. converges the incident rays towards the principal axis) which is relatively thick across the middle and thin at the lower and upper edges. The edges are curved outward rather than inward.</em>
Answer:
(a) 
(b) 
(c) 
Explanation:
(a) According to Newton's second law, the acceleration of a body is directly proportional to the force exerted on it and inversely proportional to it's mass.

(b) According to Newton's third law, the force that the sled exerts on the girl is equal in magnitude but opposite in the direction of the force that the girl exerts on the sled:

(c) Using the kinematics equation:

For the girl, we have
and
. So:

For the sled, we have
. So:

When they meet, the final positions are the same. So, equaling (1) and (2) and solving for t:

Now, we solve (1) for 

Answer:
8.5 ohms
Explanation:
from ohms law
V=IR
120=14.1R
divide both sides by 14.1
120/14.1=14.1R/14.1
R=8.5ohms