Answer:
20%.
Step-by-step explanation:
That is (60 - 50) / 50
= 10/50
= 1/5
To convert to a percent we multiply by 100:
= 20%.
Answer:
Golf ball
Step-by-step explanation:
The formula for the surface area of a sphere is 4
r². The variable is the radius. Therefore, the sphere with the smallest radius would have the smallest surface area.
Answer:
7
Step-by-step explanation:
the reciprocal of 
To find reciprocal, flip the top and the bottom.
So would be 
.
Multiply like normal.
Answer:
See below. To model with mathematics is to test ideas using math and computer programs to simulate an object or action.
Step-by-step explanation:
To "model with mathematics" means that equations and mathematical relationships will be employed to simulate an object or action instead of using the actual object or action. One example would be the design of a roller coaster. The forces inherent on a roller coaster design can be predicted using Newton's laws and other principles of physics. F=ma may be used to predict the force pulling the car down the initial incline and that can be used to calculate speed at the bottom. A change in the car's direction will also produce forces that may be calculated, One might ask "Will this turn produce more force than the seat belt can safely handle?" Rather than building a coaster and testing it with your business partner in the seat, a mathematical model can be used to determine the risks and maximum forces. You'll have a much better chance of keeping your friend intact on the actual coaster. Mathematical models are also used to predict weather, the impact of monetary policy of the economy, and even which Netflix movie you are most likely to enjoy. The design of aircraft, ships, cars, and many other items are done using computer-aided design programs where the various forces can be modeled to determine optimum design without actually building the item. This can save enormous amounts of time and money to be able to test ideas on the computer before starting actual assembly.
A+7=0
A+7-7=0-7
A=-7
B+3=7
B+3-3=7-3
B=4
