Need to know how to do both of them aswell

The graph below could be the graph of which exponential function?

The circumference of a circle is 5 pi cm. what is the area of the circle?

An assembly consists of two mechanical components. suppose that the probabilities that the first and second components meet specifications are 0.87 and 0.84. assume that the components are independent. determine the probability mass function of the number of components in the assembly that meet specifications. x