Ok , i got an assignment to collage to create a simple program that calculates salery and taxes you pay on each step of the salery, i did it and it was quite good (atleast that the instructor said),
Now he tells me to do the same but without using the && operator anywhere in the 1st case... after few hours of trying to manuver i gave up, any ideas guys?
i added my source code below thanks in advance.

ps. ignore the empty 2nd case its for another part that i already made.
Code:
#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <ctype.h>
main()
{
int l=1;
char m=0,car=0;
unsigned int income,bonus,net_income,gross_income;

 while(l)
 {
 printf("\nPress 1 for qu. 1:\nPress 2 for qu. 2:\nPress E or e to Exit:\n");
 fflush(stdin);
 scanf("%c",&m);
 switch(m)//loop so the menu will keep going unless exit is selected
 {

 case '1'://first case
  printf("Hello");
  printf("\nPlease enter your bruto salery:");
  scanf("%d",&income);
  printf("\nPlease enter your bonus:");
  scanf("%d",&bonus);
  gross_income=income+bonus;
  if(gross_income<2000)//First salery step
  {
  net_income=gross_income;
  printf("\nYour net worth is: %d",net_income);
  printf("\nCar is not approved!\n");
  }
  if(gross_income>=2000&&gross_income<=4000)//second salery step
  {
  net_income=gross_income;
  printf("Your net worth is :%d",net_income);
  printf("\nCar is not approved!\n");
  }
  if(gross_income>4000&&gross_income<=7000 )//third salery step(there no need for a check if there is a car or not becouse even if he makes 7000 bruto with bonus , he still makes less becouse of the tax
  {
  net_income=gross_income-((gross_income-4000)/5);
  printf("Your net worth is :%d",net_income);
  printf("\nCar is not approved!\n");
  }
  if(gross_income>7000&&gross_income<=10000)//forth salery step
  {
  net_income=gross_income-((gross_income-4000)/5);
  net_income=net_income-(bonus-(bonus/10));
  printf("Do you posses a company owned car press Y/N?");
  fflush(stdin);
  scanf("%C",&car);
  if(car=='y'||car=='Y')//Inner case to check if he holds a car
  {
   net_income=net_income-2000;
   printf("\n2000 nis excluded as car holding fee!\n");
  }
  printf("Your net worth is :%d",net_income);
  }
  break;
 case '2':
  printf("Hello");
  break;
 case 'e':
  printf("Hello");
  printf("\nGoodbye and have a nice day!");
  l=0;
  break;
 default:
  printf("Unknown Char please choose 1,2,E or e");
 }
 }