单选题In using Loran-C，skywave reception gives greater range but is（）.A only accurate during daylight hoursB much less accurateC only accurate at twilightD more accurate than using ground waves

已知x=range(1,4)和y=range(4,7)，那么表达式sum([i*jfori,jinzip(x,y)])的值为__________。

Student A: I wonder whether you are satisfied with the new equipment.

Student B: ______. It gives me a lot of trouble.

(A) make

(B) set

(C) arrange

(D) range

A galley grease fire on the stove may be extinguished using______．

A.water

B.foam

C.the range hood extinguishing system

D.fire dampers

In using Loran-C，skywave reception gives greater range but is ______．

A.only accurate during daylight hours

B.much less accurate

C.only accurate at twilight

D.more accurate than using ground waves

A.

func (s *Slice)Remove(value interface{}) error {for i, v := range *s { if isEqual(value, v) { if i== len(*s) - 1 { *s = (*s)[:i] }else { *s = append((*s)[:i],(*s)[i + 2:]...) } return nil }}return ERR_ELEM_NT_EXIST}

B.

func (s *Slice)Remove(value interface{}) error {for i, v := range *s { if isEqual(value, v) { *s = append((*s)[:i],(*s)[i + 1:]) return nil }}return ERR_ELEM_NT_EXIST}

C.

func (s *Slice)Remove(value interface{}) error {for i, v := range *s { if isEqual(value, v) { delete(*s, v) return nil }}return ERR_ELEM_NT_EXIST}

D.

func (s *Slice)Remove(value interface{}) error {for i, v := range *s { if isEqual(value, v) { *s = append((*s)[:i],(*s)[i + 1:]...) return nil }}return ERR_ELEM_NT_EXIST}

Which of the following is (are)an advantage of a dry chemical extinguisher over a carbon dioxide extinguisher？The dry chemical extinguisher：Ⅰ．Has a greater range．Ⅱ．Provides a heat shield for the operator．

A.Ⅰonly

B.Ⅱonly

C.Both Ⅰand Ⅱ

D.Neither Ⅰ nor Ⅱ

A.seating

B.seat

C.to sit

D.seated

Loran-C is which type of navigation system ________．

A.Hyperbolic，long-range navigation system

B.Short-range electronic

C.Long-range，high frequency navigation system

D.Long-range，with a frequency of 1950 kHz