I’m not sure abt 21 but 22 is the second one and the 4th one. So 2,4.
Answer:
To find the surface area of a cube, use the formula: surface area = 6s^2, where s is the length of one of the sides. If you don't know the length of the sides, you can find the surface area using volume. Just find the cube root of the volume, which is equal to the length of one side of the cube.
Step-by-step explanation:
Answer:
5.09 × 10^-2
Step-by-step explanation:
You have to take the number go to the decimal and move it until you get to the first number and in this case, it is 5 put the decimal there. To write it you have to count the number of times you moved the decimal. when doing this it will always be a number times 10^ the number you moved the decimal.
8.4 because 6 would round up to 10 and 10+30 =40 for 8.40 or just 8.4
