1) Starting with a large task and breaking the process into small tasks.
These tasks are more simple to complete. The tasks are then interrelated
to complete given task. 
 steps to follow 
  a) Clearly state the problem that you are trying to solve. 
  b) Define the inputs required by the program and the ouputs to be
  produced.
  c) Design the algorithm. 
  d) turn the algorithm into fortrna statements. 
  e) Compile, run and test the program. 

2)  
 
PROGRAM greatest

IMPLICIT NONE
INTEGER :: n1, n2, n3, big, small 

READ(*,*) n1,n2,n3 
if(n1 > n2) then 
   big = n1
   small = n2
else 
   big = n2 
   small = n1
END IF
if(n3 > big) then   
 big = n3
 elseif (n3 < small) then
    small = n3
endif 
write(*,*) 'The Biggest Number is ', big 
write(*,*) 'The smallest Number is ',small 
 
END PROGRAM greatest


program SORT

IMPLICIT NONE
integer n1,n2,n3,middle,big,small
read(*,*) n1, n2, n3
middle = n3
if(n1 > n2) then 
   big = n1 
   small = n2
else 
   big = n2 
   small = n1
endif

if (n3 > big) then
   middle = big
   big = n3
else if (n3 < small) then 
   middle = small
   small = n3
endif

write(*,*) 'The sorted order is ',big, middle, small

END PROGRAM SORT


3) 

PROGRAM grades
IMPLICIT NONE

integer :: score

READ(*,*) score

temp :SELECT CASE (score)
      CASE (70:) 
         Write(*,*) "Student gets Distinction"
      CASE (60:69)
         Write(*,*) 'Student gets Ist Class'
      CASE (50:59) 
         Write(*,*) 'Student gets IInd Class'
      CASE (40:49) 
         Write(*,*) 'Student gets Pass Class'
      CASE DEFAULT
         Write(*,*) 'Student fails'
 
   END SELECT temp

END PROGRAM grades

4) 

  a) infinity 

  b) 10 

  c) 1

  d)  error

  e) 3

a) 1i = -00123
b) A =   1.002000E+06 B =   0.100010E+07 Sum  =   0.200210E+07 Diff =   1900.000000
c)  result =      F 


5) program real
real :: pi


35 FORMAT(F7.4)
40 format(A25)
50 format(A30)

write (*,40,ADVANCE='NO') "Enter the valur of pi "
read(*,*)pi
write(*,50,ADVANCE='NO') " The value of pi entered is "
write(*,35)pi



end program