Many different species of songbirds migrate into the united states and canada from central and south america each summer in order to take advantage of the caterpillars and other insects that hatch in the northern forests during the summer. over the past several decades songbird populations have been declining. how might a decrease in the number of songbirds be expected to affect the trees in a northern forest? the trees would not be affected if there were fewer songbirds since the birds only eat insects and would not be feeding off the trees. the trees would stop growing if herbivorous insects damaged their leaves at all, so there would be very little new growth in the forests. the trees would suffer more leaf damage as herbivorous insect populations increased until the populations of other insect predators increased in response. the trees would produce more seed since fewer birds were there to eat, and more young trees would begin to grow up in the forests.

The correct statement is the third one, that is, the trees would suffer more leaf destruction due to the growth of the insects.

Explanation:

The songbirds, which migrate to the northern forests at the time of summer, consume caterpillars and insects that hatch during the same time. Therefore, songbirds are the predators, and the caterpillars and insects are the prey. Hence, if there will be a reduction in the population of songbirds, it will ultimately result in the elevation of the population of caterpillars and insects. As the caterpillars and insects feed on the leaves of the plants, it will result in more destruction to the leaves and it will continue until and unless insect predators get an increase in the environment.

1. (1.2kw)x(15/60hours) = .3kwh --> a

2. (5kw)x(90/60hours)x(8cents/kwh) = $0.60 --> d

3. microwave --> 1200 watts = (1.2kw)x(6/60hours) = .12kwh

coffee-maker --> 900 watts = (.9kw)x(10/60hours) = .15kwh

therefore, it requires more energy for the coffee-maker to do the same amount of work.

so the answer is a.

the level of progesterone is low at the pre-ovulatory phase of the cycle but it gradually increases and the levels are high at the luteal phase. if pregnancy occurs, the level of progesterone will be high throughout the pregnancy.

if egg is fertilized and the mother gets pregnant, progesterone starts preparing the uterus for the implantation. it starts building up the lining of uterus and make it hostile of the period of pregnancy.