Answer:
1. sin∠EDA is equal to sin∠EBC
2. sin∠CEB is not equal to sin∠EBC
3. cos∠BEC is equal to sin∠EBC
4. cos∠ADE is not equal to sin∠EBC
5. sin(90 - m∠EBC) is not equal to sin∠EBC
6. cos(90 - m∠EDA) is equal to sin∠EBC
Explanation:
From inspection of the given diagram, ∠EAD = ∠ECB = 90°.
According to the vertical angles theorem, ∠BEC = ∠DEA.
According to AA similarity theorem, ΔADE ~ ΔCBE
Therefore, ∠EDA = ∠EBC.
This means that:
- sin∠EDA is equal to sin∠EBC
- sin∠CEB is not equal to sin∠EBC

Since cos∠BEC = CE/BE and sin∠EBC = CE/BE then:
- cos∠BEC is equal to sin∠EBC.
As ∠BEC ≠ ∠ADE then:
- cos∠ADE is not equal to sin∠EBC.
As sin(90° - x) = cos(x) then sin(90 - m∠EBC) = cos∠EBC.
As cos∠EBC ≠ sin∠EBC then:
- sin(90 - m∠EBC) is not equal to sin∠EBC
As cos(90° - x) = sin(x) then cos(90 - m∠EDA) = sin∠EDA.
As sin∠EDA = sin∠EBC then cos(90 - m∠EDA) = sin∠EBC.
Hence:
- cos(90 - m∠EDA) is equal to sin∠EBC.