Twice the sum of a number and 400. Translate the verbal expression into an algebraic expression plz

There a total of 82 students in the robotics club and the science club. the science club has 6 fewer students than the robotic club. how many students are in science club?

What is the effect on the graph of the function f(x)=x when f(x) is replaced with -f(x)+4

Onnie is considering doing some long term investing with money that she inherited. she would like to have $50,000 at the end of 30 years. approximately how much money would lonnie need to put into an account earning 6% interest compounded annually in order to meet her goal?