We have the next diagram
Where N is the normal and W is the weight
Therefore
N=W
The formula to calculate the W is
![W=mg](https://img.qammunity.org/2023/formulas/physics/college/mwp20nloxyakj67s56rj7ugdcwo94t9z7k.png)
where m is the mass and g is the gravity
In our case,
m=55
g=9.8 m/s^2
![W=55(9.8)=539N](https://img.qammunity.org/2023/formulas/physics/college/t8g38pgnit8jtexudnv9pawbzibogrwsyi.png)
Therefore the normal force
N=539N
ANSWER
the normal force is 539N