质点在oxy平面内运动,运动学方程为 r =2t i +(19-2t 2 ) j ,均为国际制单位。则t=1s时的切向加速度的大小为________________,法向加速度的大小为________________________,质点所在处轨道的曲率半径为________________.(备注:由于网站自带的公式编辑器无法打出矢量符号,故矢量用加粗体表示;答案保留小数点后两位)
【单选题】Consider two mutually exclusive projects A & B. If you subtract the cash flows of opportunity B from the cash flows of opportunity A, then you should:
A.
take opportunity A if the regular IRR exceeds the cost of capital.
B.
take opportunity A if the incremental IRR exceeds the cost of capital.
C.
take opportunity B if the regular IRR exceeds the cost of capital.
D.
take opportunity B if the incremental IRR exceeds the cost of capital.