Express 0.000000298 as a single digit times a power of. ten rounded to the nearest ten millionth

Atriangle has a side lengths of 18cm, 80 cm and 81cm. classify it as acute obtuse or right?

Cody was 165cm tall on the first day of school this year, which was 10% taller than he was on the first day of school last year.

Aadc is formed by reflecting aabc across line segment ac, as shown in the figure. if the length of ac is 4 units, the area of aadc is square units.