Mary’s parents gave her $60 as pocket money to meet her daily expenses. she spent $20 on clothes and $10 on food. she wishes to buy some books, also. if each book costs $3 each, solve the inequality to find how many books she can buy. question 5 options: at the most 10 at least 10 10 at the most 5

Having a hard time understanding this question (see attachment).

The weight of a radioactive isotope was 96 grams at the start of an experiment. after one hour, the weight of the isotope was half of its initial weight. after two hours, the weight of the isotope was half of its weight the previous hour. if this pattern continues, which of the following graphs represents the weight of the radioactive isotope over time? a. graph w b. graph x c. graph y d. graph z

Long division setup showing an incomplete calculation. 12 is in the divisor, 6839 is in the dividend, and 5 hundreds and 6 tens is written in the quotient. 6000 is subtracted from 6839 to give 839. an unknown value represented by a box is being subtracted from 839. what number should be placed in the box to complete the division calculation?