在光滑的水平面上做匀加速直线运动的物体，当它所受的合力逐渐减小而方向不变时，物体的（　　）

A．加速度越来越大，速度越来越大

B．加速度越来越小，速度越来越小

C．加速度越来越大，速度越来越小

D．加速度越来越小，速度越来越大

• (A) 条件(1)充分，但条件(2)不充分．
• (B) 条件(2)充分，但条件(1)不充分．
• (C) 条件(1)和(2)单独都不充分，但条件(1)和条件(2)联合起来充分．
• (D) 条件(1)充分，条件(2)也充分．
• (E) 条件(1)和条件(2)单独都不充分，条件(1)和条件(2)联合起来也不充分．

Automobile A is traveling at two-thirds the speed that Automobile B is traveling. How fast is Automobile A traveling
(1) If both automobiles increased their speed by 10 miles per hour, Automobile A would be traveling at three-quarters the speed that Automobile B would be traveling.
(2) If both automobiles decreased their speed by 10 miles per hour, Automobile A would be traveling at half the speed that Automobile B would be traveling.