Aruler has markings as shown below. stefan uses this ruler to measure the length of a metal rod.
10
20
how many decimal places should his answer include?
02

Ijust need these 2 questions answered (the second pic is just confirmation i'm not confident in that answer)

Serena is making an experiment. for that, she needs 20 grams of a 52% solution of salt. she has two large bottles of salt water: one with 40% and the other with 70% of salt in them. how much of each must she use to make the solution she needs? i am in need of

15 oranges weigh 3.75 kilograms (kg). if each orange weighs approximately the same, approximately how much does each orange weigh?