在如下图所示的食物网中,已知各营养级之间的能量转化效率为10%,若一种生物摄食两种上一营养级的生物时,两种被摄食的生物量相等,则丁每增加10千克生物量,需消耗生产者戊多少千克?()
A. 3250kg
B. 4500kg
C. 4750kg
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Whatindicatesthatatropicalcyclonemaybewithin500to1,000milesofyourposition?()
Apumpingofthebarometerupanddownafewmillibars
B. Asuddenwindshiftfromsouthwesttonorthwestfollowedbysteadilyincreasingwinds
C. Thenormalswellpatternbecomingconfused,withthelengthoftheswellincreasing
D. Anovercastskywithsteadilyincreasingrainfromnimbostratusclouds
Are-heaterinanairconditioningsystemfunctionsto().
A. controlinletairtemperature
B. controlinletairvolume
C. maintainrelativehumidityat15%
D. restoreconditionedairtemperaturetoacomfortablelevel
Whenadeckcargoissecuredwithchainorwirelashingsandgrab(pear)links,whichstatementisFALSE?()
A. Theamountoftake-upislimitedbythelengthoftheturnbuckle
B. Atthegrab(pear)link,theslackendofchainshouldbeledbackandsecuredtothechainabovethelink
C. Thelashingsshouldbeinspectedeachdayandanyslacktakenup
D. Theturnbuckleshouldbesecuredwithastickorlocknuts
企业日常存货的发出方法有()。
A. 先进先出法
B. 加权平均法
C. 移动平均法
D. 个别认定法
E. 后进先出法