m = mass of the truck traveling = 2500 kg
v = speed of the truck traveling = 75 km/h = 75 (km/h) (1000 m/ 1 km) (1 h /3600 sec) = 20.83 m/s
h = plank's constant = 6.63 x 10⁻³⁴
λ = wavelength of truck = ?
according to de broglie's principle, wavelength of truck is given as
λ = h/(mv)
inserting the values in the above equation
λ = (6.63 x 10⁻³⁴)/((2500) (20.83))
λ = 1.3 x 10⁻³⁸ m
5 g of potassium oxalate react to produce 0.03 moles of calcium oxalate.
Calcium oxalate (CaC₂O₄) is obtained by the reaction of 5 g of potassium oxalate (K₂C₂O₄).
We can calculate the moles of CaC₂O₄ obtained considering the following relationships.
- The molar mass of K₂C₂O₄ is 184.24 g/mol.
- The mole ratio of K₂C₂O₄ to CaC₂O₄ is 2:1.

5 g of potassium oxalate react to produce 0.03 moles of calcium oxalate.
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Explanation:
Hello mr/mrs (name) I unfortunately couldn't pay attention to the class due to some issues I had therefore I don't know what we are doing in class
OR
Hello mr/mrs (name) I could understand what we were doing in class I would like it if you could break it down more or explain better to me
OR just say something it had something to do with your internet such as
Hello mr/mrs (name) I didn't understand what you were saying during our class due to some of my internet issues I was have throughout the day. I hope you can explain what we did during the class.
Those may be some of my excuses I've used before
they have worked for me:)
I don't know if that helped?:/
The answer is C) iron and oxygen. The reactants are on the left side of the equation