A poll of 250 students found they studied an average of 48 minutes each evening with a standard deviation of 8.4 minutes. Using a 90% confidence interval, what is the maximum error of estimate for the time spent
studying?
A
1.04
B
1.37
C
1.99
D
0.87

Which of the following graphs could represent a cubic function?

White shapes and black shapes are used in a game. some of the shapes are circles. while the rest are squares. the ratio of the number of white shapes to the number of black shapes is 5: 11. the ratio of the number of white cicrles to the number of white squares is 3: 7. the ratio of the number of black circles to the number of black squres is 3: 8. work out what fraction of all the shapes are circles.

3. a sum of $2700 is to be given in the form of 63 prizes. if the prize is of either $100 or $25, find the number of prizes of each type.