Is it true that any marking on an angle means that the angle measure 90 degrees?

What is the average speed of a car that travels 40 mph for 1 hour and 60 mph in another hour?

The electric field direction is defined by the direction of the force felt by (select one of the following answers): 1. a negative charge. 2. a positive charge. 3. both positive and negative charges.

Atruck driver is attempting to deliver some furniture. first, he travels 8 km east, and then he turns around and travels 3 km west. finally, he turns again and travels 13 km to his destination. what is the drivers distance