I need help ASAP. The cone shown has a 3 in radius and 7 in height. What is the volume of the composite figure?

What is (28 + 7 + 6 + 3) x 1/2 show your work

What is the number 321,000,000 in scientific notation? also what is the number? ?

If m∠abc = 70°, what is m∠abd? justify your reasoning.  using the addition property of equality, 40 + 70 = 110, so m∠abd = 110°.  using the subtraction property of equality, 70 − 30 = 40, so m∠abd = 30°.  using the angle addition postulate, 40 + m∠abd = 70. so, m∠abd = 30° using the subtraction property of equality.  using the angle addition postulate, 40 + 70 = m∠abd. so, m∠abd = 110° using the addition property of equality.