Q:

A) 9 and 3 kmph | B) 6 and 7 kmph |

C) 8 and 1 kmph | D) 7 and 2 kmph |

Answer: C) 8 and 1 kmph

Explanation:

Explanation:

Downstream speed = 72km/8hrs = 9 kmph

upstream speed = 84km/12hrs = 7 kmph

speed of boat = avg of downstream and upstream speeds

speed of boat = (9+7)/2kmph = 8 kmph.

current speed = half of the difference of downstream and upstream speeds

currend speed = (9-7)/2kmph = 1 kmph

4
1005

5
920

1
743

4
897

1
867

1
1941

Q:

A) 2(2 + √17) | B) 3(2 + √17) |

C) 2(4 + √15) | D) 3(4 + √17) |

3
1745

Q:

A) 0.20 Hz | B) 625 Hz |

C) 250 Hz | D) 100 Hz |

2
1460