int main()
{
float D,d, l, area, v;
printf("Escriba el diámetro mayor:");
scanf("%f",&D);
printf("Escriba el diametro menor:");
scanf("%f",&d);
printf("Escriba la longitud:");
scanf ("%f", &l);
if (D<d)
{
printf("error");
}
else (D>d);
{
area = d/2 + 2/3(D/2 - d/2); //HERE IS THE ERROR, and it says "error '3' cannot be used as a function", please i need help//
}
v = Pi * l * area;
printf("El volumen es %f", v);
return 0;
}