Write 0.00968 in scientific notation

The distribution of the amount of money spent by students for textbooks in a semester is approximately normal in shape with a mean of $235 and a standard deviation of $20. according to the standard deviation rule, how much did almost all (99.7%) of the students spend on textbooks in a semester?

The holiday party will cost $160 if 8 people attend.if there are 40 people who attend the party, how much will the holiday party cost

In the diagram, ab is tangent to c, ab = 4 inches, and ad = 2 inches. find the radius of the circle.