I don’t understand how to do this

(if f(x)=4x^2 and g(x)=x+1, find (f o g)(x)

How many lines can be drawn through points j and k? 0 1 2 3

Jada has a meal in a restaurant she adds up the prices listed on the menu for everything they ordered and gets a subtotal of $42.00. when the check comes, it says they also need to pay $3.99 in sales tax. what percentage of the subtotal is the sales tax