A) Experiments. Opinion polls are used to study people, intuition and imagination are not official studies. Would appreciate brainliest!
Answer:Speed can be defined as
Explanation: B because if you think about it, 50 milers per hour means they are dividing the time it takes to drive a certain distance going that speed. So id has to be answer B! your welcome. Please upvote only if its correct!
Answer:
The cart would speed up.
Explanation:
According to Newton's 1st law, object subjected to no force, or net force 0, would have a constant speed. In our case the cart is initially at constant speed, meaning the man exerts a force that is equal to friction force. If he increases the force on the cart, the net force would no longer be 0. The cart would gain an acceleration and increases its speed.
Radioactive "decay" means particles and stuff shoot OUT of a nucleus.
After that happens, there's less stuff in the nucleus than there was before.
So the new mass number is always less than the original mass number.