Mandy is testing an unknown solution to determine whether it is an acid or a base. she places a piece of red litmus paper into the solution and the paper turns blue. what is her unknown solution?

Gravity is pulling an object into the sun. the closer the object gets to the sun, the greater the gravitational force that acts on the object, increasing its acceleration. a line graph plotting the speed of the object against time would have which shape? a: straight line of positive slope b: curved line that slopes upward c: curved line that slopes downward d: straight line of negative slope