Propose a structure for the following compound that fits the following ¹H NMR data: 
Formula: C₂H₄O₂                      
¹H NMR:
2.1 δ (singlet, 1.2 cm)
11.5 δ (0.5 cm, D₂O exchange)

Identify each of the following compounds from its molecular formula and its IR and ¹H NMR spectra.

d. C₄H₈O₂

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Propose a structure for the following compound, C₇H₁₂O₂ with the given ¹³C NMR spectral data: 

Broadband decoupled ¹³C NMR:19.1, 28.0, 70.5, 129.0, 129.8, 165.78 δ 

DEPT-90:28.0, 129.8 δ 

DEPT-135:19.1 δ (↑), 28.0 δ (↑) , 129.8 δ (↑) , 70.5 δ (↓) & 129.0 δ (↓)

Propose a structure for the following compound that fits the following ¹H NMR data: 

Formula: C₃H₈O₂              

¹H NMR:

3.36 δ (6H, singlet)

4.57 δ (2H, singlet)

Propose a structure for the following compound that fits the following ¹H NMR data: 

Formula: C₁₀H₁₄                   

¹H NMR:

1.2 ppm (6H, doublet)

2.3 ppm (3H, singlet)

2.9 ppm (1H, septet)

7.0 ppm (4H, doublet)

Propose a structure for the following compound, C₅H₁₀O with the given ¹³C NMR spectral data: 

Fully Broadband decoupled ¹³C NMR and DEPT: 206.0 δ (↑); 55.0 δ (↑); 21.0 δ (↓) & 11.0 δ (↑).

Provide the structure of the unknown compound from the given information. 

Formula: C₄H₁₀O      

IR: 3200-3600 cm^-1      

¹H NMR:

0.9 ppm (6H, doublet) 

1.8 ppm (1H, nonatet) 

2.4 ppm (1H, singlet) 

3.3 ppm (2H, doublet)

Provide the structure of the unknown compound from the given information. 

Formula: C₄H₉N       

IR: 2950 cm^-1, 3400 cm^-1    

¹H NMR:

1.0 ppm (4H, triplet) 

2.1 ppm (4H, triplet) 

3.2 ppm (1H, singlet)