please help me with these questions in mathematics................................

1.Mr.Harikishan is out of station for seven days.He returns home on monday morning.He observes a snail making its way up the wall of your cabin.Each day,it carefully works its way 2.5m up the wall.At night,though,it slips back down 1 metre.The cabin wall is 9 m high.If the snail started on monday,when will it reach the top of the cabin wall ?
a)Friday morning 2)saturday evening 3)Thursday morning 4)monday morning

2.A log of wood has 33 kg weight.A group of termites started eating it.Everyday , these termites eat 10000 mg of wood.In how many days will the group of termites eat the whole log of wood?
a) 3300 days b)33 days c)303 days d)330 days



1 kg =1000000 mg
so 33 kg=33000000mg
 total days=wt.of wood/wt.of daily loss
ans....3300  option A
ans1)total distance in one night and day=2.5-1=1.5m
total days required=total distance/distance in one night and day
so....answer is saturday eve

1. saturday evening

net distance covered in each day = 1.5m

after 5th day, distance covered = 1.5 * 5 = 7.5m

on 6th day it covers 1.5m in day time & reaches the top..

3300 days

10000mg = 0.01kg

33kg = (33/0.01) days = 3300days