Please help me with this, I'm on a test! Also, please explain how you got your answer.

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

Ming says that 0.24 > 1/4 because 0.24= 2/4. which best explains mings error

Jessa bought a yoyo from a company that claims that, with each retraction, the string rolls up by 60% of the original length. she sets up a tape measure and throws the yoyo 3 times. her data are charted below. throw length of string (feet) 1 3 2 1.8 3 1.08 jessa wants to find the sum of the length of string after 10 throws. what is the sum of the lengths, rounded to the nearest hundredth?