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 

The answer is D I took the test
Answer:
Food, clothes, language, and belief
the upside down image means an inverted image and for an inverted image, magnification is negative
so the answer is -m
Circuit breaker is a device that is designed to open an overloaded circuit and prevent overheating. The correct option in regards to the given question is option "a". The main purpose of the circuit breaker is to disconnect the defective switch from the circuit as soon as any problem arises. This helps in preventing any kind of major accident. Overheating can result in a big accident and the circuit breaker is the device that senses the overheating and disconnects the switch before any major incident. It is an automated system that acts as a protective devise.