Astudent reduces the temperature of a 300 cm3 balloon from 60°c to 30°c. what will the new volume of the balloon be? (remember to be careful with the units.)

Suppose you are choosing a 6-digit personal access code. this code is made up of 4 digits chosen from 1 to 9, followed by 2 letters chosen from a to z. any of these digits or letters can be repeated. find the total number of personal access codes that can be formed. 492,804 341,172 39,917,124 4,435,236

In the next 10 month, colin wants to save $900 for his vacation. he plans to save $75 each of the first 8 months. how much must he save each of the last 2 months in order to meet his goal if he saves the same amount each month ?

The coverage of a base station of a telecommunication company forms a disk with a radius of (kilometers). let be the distance of a cellphone from a base station. assume that the location of cellphones in use are randomly uniformly distributed within the disk. calculate the mean and variance for the random variable.