In recent years the annual productivity of slash-and-burn systems has tended to decline over that achieved by the traditional shifting cultivation systems of the past. To what is this decline most likely due?
A) reduction in the C/N ratio of the soil organic matter
B) reduction in the use of fertilizers
C) increase in the period of food production in a given cycle
D) failure to grow legumes in the cropping system
E) decrease in the length of the fallow period
E
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Technician A says a transmission band is hydraulically applied by a multiple disc clutch.Technician B says that for the PCM/TCM to determine when to start a gear change, it must be able to refer to shift schedules that it has stored in its memory.Who is correct?
A. Technician A B. Technician B C. Both A and B D. Neither A nor B
A labor crew for placing concrete consists of one labor foreman at $26.70 per hour, one cement finisher at $29.30 per hour, five laborers at $24.45 per hour each, and one equipment operator at $33.95 per hour. Such a crew, called a C20 crew, can place 165 cubic yards of concrete per 8-hour day. Determine (a) the cost per day of labor for the C20 crew, (b) the cost of the C20 crew per cubic yard of concrete, and (c) the cost to place 550 cubic yards of concrete.
What will be an ideal response?
A clock pendulum and the agitator of a top-loading washing machine move with a(n) ____ motion.
A. linear B. reciprocal C. rotary D. oscillating
A voltage signal is cycling at a fixed rate from 0 to 12 volts. The ratio of on-time relative to the period of the cycle is the ________
A) Duty cycle B) Amplitude C) Frequency D) Pulse width modulation