How can the mantle flow by convection if it is a solid?

Alaina wants to decide whether her current cell phone plan is better than a package that another company offers. to compare the two plans, she plotted two lines on a graph, where y represented the total cost of one month’s service and x represented the megabytes of data that she used in a month. which part of the graph will represent the cost per megabyte of data used in each plan?

What are the answers for the following questions?

Ascientist is explaining how background cosmic radiation gives evidence of the big bang theory. she says that radiation has been detected everywhere equally as heat in the universe and is increasing. this has been shown to be residual radiation from the big bang. what error did the scientist make?