Hello! Hope everyones doing ok. could use your help here: 1. Draw 16 stairs. Put them equally into 2 sets. How many stairs are in each set? ___

2. Round each number to the nearest 10. Then subtract : 497 - 315 is about: ___

3. Abel drew some Triangles. his drawing had 21 Vertices. How many triangles did he draw? write a division equation to answer the question: ___

What is the approximate circumference of the circle shown below?

Ariana starts with 100 milligrams of a radioactive substance. the amount of the substance decreases by 20% each week for a number of weeks, w. the expression 100(1−0.2)w finds the amount of radioactive substance remaining after w weeks. which statement about this expression is true? a) it is the difference between the initial amount and the percent decrease. b) it is the difference between the initial amount and the decay factor after w weeks. c) it is the initial amount raised to the decay factor after w weeks. d) it is the product of the initial amount and the decay factor after w weeks.

If the probability of an event happening is 65% then the probability this event does not occur?